Electrical Noise onboard

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Hi, I´m thinking on lowing my electrical noise onboard but not sure whitch way could be better. My main idea is to use the o-scope to measure all VPK-PK and try to low them down as far as I can. But what about frecuencies? It´s it posibble to use the Scope to view the fundamental one and try to figure out if it´s getting on 35 mhz?

Another question I got in mind, which impedance is used in the futaba standar TX antenna? 50 omh?

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Is it possible to use the Scope to view the fundamental one and try to figure out if it´s getting on 35 mhz?

Sadly, an o-scope won't help much for EMI/RFI testing. The responsible signals you need to measure are not readily seen with such an instrument. As mentioned, this is the job for a decent Spectrum analyzer.

If it were only so easy. I'm more interested in a Network analyzer than a Spectrum analyzer. They are similar, but the Network analyzer will certainly have a useful tracking generated in it, whereas that is not always the case for the other. I've been watching ebay for a couple years looking for a decent model of either that has had a recent calibration. Because bench space is at a premium, the usual 25 year old massive beast won't work for me. There are a lot of fair deals in the $5K to $15K USD range, but that is beyond my budget. So, I am still on the hunt ...

I have found no way to test for problem noise apart from flying the plane and testing the range, change something and fly again. I aim to use good practice and avoid known problems.

Although my usual tests are done without flying, I agree that this is a great way to check for EMI/RFI noise. It is quite effective too, but not as convenient and absolute as using engr test equipment. But without a spectrum analyzer, and the experience to use it, this is not a bad way to test and resolve the noise issues.

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I've been watching ebay for a couple years looking for a decent model of either that has had a recent calibration. Because bench space is at a premium, the usual 25 year old massive beast won't work for me. There are a lot of fair deals in the $5K to $15K USD range, but that is beyond my budget. So, I am still on the hunt ...

Funny, looks like we're all looking for that killer deal on eBay, I guess that's just one of those things that'll never happen, an EE's dream so to speak. When I do win some money in the lottery though, that money is going towards equipment rather than a car or something, a ~2GHz scope and a ~10GHz spectrum analyzer have been on my Christmas wishlist for quite some time now

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a ~2GHz scope and a ~10GHz spectrum analyzer have been on my Christmas wishlist for quite some time now

I know what you mean. I have a TEK Spectrum Analyzer, which is good up to 21Ghz. It works great for measuring video and R/C transmitters, which covers a lot of ground for me. But I'm jones'n for a Network Analyzer of better caliber. Given the budget issues, I think I will just find a tracking generator for my TEK instead. But it would be nice to avoid the additional workbench clutter, so I still keep one eye on eBay for a killer deal.